27 lines
435 B
Go
27 lines
435 B
Go
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package main
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import (
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"context"
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"fmt"
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)
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func main() {
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traceCtx := context.WithValue(context.Background(), "trace_id", "12-21-33")
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makeRequest(traceCtx)
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}
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func makeRequest(ctx context.Context) {
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oldValue, ok := ctx.Value("trace_id").(string)
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if ok {
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fmt.Println(oldValue)
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}
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newCtx, cancel := context.WithCancel(ctx)
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defer cancel()
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newValue, ok := newCtx.Value("trace_id").(string)
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if ok {
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fmt.Println(newValue)
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}
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}
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